The Havran-Balıkesir Fault Zone (HBFZ) is one of the major active structures of the Southern Marmara Region, which has been shaped by the southern branch of North Anatolian fault since the Pliocene. HBFZ is a 10–12 km wide, 120 km long, right-lateral strike-slip fault zone that consists of two ENE-striking main faults, namely, the Havran-Balya and Balıkesir faults. The 90-km-long Havran-Balya fault exhibits right-stepping en echelon geometry and is made up of (1) Havran, (2) Osmanlar, (3) Turplu and (4) Ovacık fault segments. On the eastern part, the 70-km-long Balıkesir fault is divided into two fault segments; (1) Gökçeyazı and (2) Kepsut. We estimated the long-term slip rate between 3.59 and 3.78 mm/yr using river offset. The Kepsut, Gökçeyazı and Ovacık fault segments are capable of generating an earthquake with a moment magnitude of up to 7.2. Detailed palaeoseismological studies show that the HBFZ is responsible for some surface faulting earthquakes with an average recurrence interval of 1000–2000 years during the late Holocene. Considering the fact that there was no evidence of a surface-ruptured earthquake for 2000 years, it can be stated that there is a seismic gap on the Gökçeyazı fault segment.

中文翻译：

---

Havran-Balıkesir 断层带的古地震学：土耳其西北部安纳托利亚北部断层南支走滑主导的收缩变形中过去地震的证据

Havran-Balıkesir 断层带（HBFZ）是南马尔马拉地区的主要活动构造之一，自上新世以来一直由北安纳托利亚断层的南支形成。HBFZ 是一个宽 10-12 公里、长 120 公里的右旋走滑断裂带，由两条 ENE 走向的主断层组成，即 Havran-Balya 和 Balıkesir 断层。90 公里长的 Havran-Balya 断层显示出右阶梯梯形几何形状，由 (1) Havran、(2) Osmanlar、(3) Turplu 和 (4) Ovacık 断层段组成。在东部，70 公里长的 Balıkesir 断层分为两个断层段；(1) Gökçeyazı 和 (2) Kepsut。我们使用河流偏移量估计了 3.59 至 3.78 毫米/年的长期滑移率。Kepsut、Gökçeyazı 和 Ovacık 断层段能够产生高达 7.2 级的地震。详细的古地震学研究表明，HBFZ 是全新世晚期平均重复间隔为 1000-2000 年的一些地表断层地震的原因。考虑到 2000 年来没有地表破裂地震的证据，可以说 Gökçeyazı 断层段上存在地震间隙。